Monday, November 21, 2011

Most of the time I had the problem, the YouTube downloader software doesn't work properly. Also some times IDM is going wild. So most of the time I was in trouble while downloading some videos from you tube. So after some look-up here and there I found KeepVid (http://www.keepvid.com/) is a good solution for download videos from streaming sites consistently. So guys try it out. You can use it freely on line. It can Download videos fromYoutube, GoogleVideo, Break.com, Dailymotion,
Blip.tv, Groper, Current TV etc also it can Download videos directly from the video webpage.

Sunday, November 20, 2011

This is really interesting. Try it out.
The ffdshow is
DirectShow and VFW codec for decoding/encoding many video and audio
formats, including DivX and XviD movies using libavcodec, xvid and other
opensourced libraries with a rich set of postprocessing filters.You can do so many things with this. It is all open source.

Friday, November 18, 2011

Our Intelligent Traffic Light System is capable of changing priority level of the roads according to their traffic level. To measure the traffic level we have several mechanisms.

Image Processing

Pressure sensors, give reading when pressure changes by the vehicles

Inductive Loops

From the above methods we choose inductive loop.It is build on the concept of inductance change of a coil when a metal object come closer.You know that when you send electrical current through a wire, it generates a magnetic field. For a coil this electromagnetic field is high.You can change the inductance of the coil and change the electromagnetic flux by introducing additional conductive materials into the loop's magnetic field. This is what happens when a car pulls up to the intersection. The huge mass of metal that makes up your car alters the magnetic field around the loop, changing its inductance.

So we have made a coil develop the inductive loop.We have some kind of metering device to meter the voltage level change in the coil. After some reading we have found this article, it really help to achieve our target.

In the above circuit diagram we can connect the LED's positive pin to PIC device to get the input. So using that we can easily develop a algorithm to achieve dynamic traffic controlling.

References : Above diagrams and pictures are extracted from the following resources on the purpose to gather all the knowledge in to one place for learn easily.

Next Task was to make the controlling mechanism for traffic lights. Major problem was, there are not enough I/O pins in the PIC to control each bulb of the traffic light. So we choose small mechanism to avoid that problem. That is the 8*6 LED Matrix. To explain this concept I will use a article publish by electronic department of our university. (http://www.ent.mrt.ac.lk/web/knowledgebase/uc/5.3.pdf) . Here we use the mechanism used to light up pixels in a LCD display. I will explain the steps to light up all the 40 LEDs using this mechanism at same time.

To light a single LED in this matrix we have to give +,- voltages to its pins. You can notice that if we set any pin in PORTB to logic 1, it will give + voltage to LED's + pin.

Then How we can give the ground connection to the - pin of the LED. For that we have to turn on the D400 transistor for that particular column.

After that particular LED will be light up. For example we can use this code to light up all the LEDS RA0 column,
PORTB=0b11111111;
PORTA=0b00000001;

To light up all the LEDS RA1 column,
PORTB=0b11111111;
PORTA=0b00000010;

To light up all the LEDS RA2 column,
PORTB=0b11111111;
PORTA=0b00000100;

To light up all the LEDS RA3 column,
PORTB=0b11111111;
PORTA=0b00001000;

To light up all the LEDS RA4 column,
PORTB=0b11111111;
PORTA=0b00010000;

To light each other LED in RA0 Column you can use this code,
PORTB=0b10101010;
PORTA=0b00000001;

Like that we can control each LED in a column using PORTB pins.But you can identify that you cant light up RA0 columns 0the row LED and off the RA1 columns 0the row LED at the same time. Because we use PORTA pins to choose the column and PORTB to choose the row.

So how can we light up all the columns at same time. We use the weakness of human eye to this.If we light different columns at high speed you cant see a difference you will notice that all the LEDs are lighting at the same time.

To use this device in the mood working 100% correct, we have to use a resistor divider to reduce the operating Because PIC18f452's RX,TX operating in 5V-0V range but in this Bluetooth reviver it operates in 3.3V to 0V range. So we put up a voltage divider between the Arduino Bluetooth Module Slave Wireless Serial Port and the PIC's RX, TX pins. After setup according to the below diagram Bluetooth Module will start working. When you search for new Bluetooth it will appear as a other type of device.You can couple the device with your laptop using its embedded pin code. After that your PC will have a serial port open via Bluetooth. you can easily communicate with that.

For the Semester 4 of the Computer Engineering Department of University of Moratuwa, we learn a subject call Micro-Controllers and Applications. The aspect of this to learn the way of handling Micro-Controllers in their limited environment. For the project of this subject some of we have been asked to build a intelligent traffic light system.To describe it's functionality read this,

Control of the road traffic on junctions :

Up to maximum of 4 roads are intersecting with 4 pedestrians crossings in each road, near the junction. This will be the extreme, but system will be able to control all the other subset of junctions.

Dynamic priority level for roads :

This system will be able to sense all the vehicle movements through the junction.After sensing these movements, the system will adjust its timing parameters automatically to give the higher priority to roads which have much traffic level.

Ability to configure system easily after installation:

After installing the traffic light system in the roads, the configurations can be changed by plugging a simple interface to the system.

Manual Override:

When a Police Officer does traffic controlling, he will be able to control all the traffic lights using a remote control device.

Fail Safe :

If something goes wrong, the system should be able to move into state which will stop all the movements of vehicles and people, which will cause further damage.

Energy Saving:
Should be able to control the intensity of the lights in the night and day time.

Automatic roll back to auto mood:

If system has been changed to manual mood and if there are no commands issued to the system for a particular time period it switches back to auto mood.

Can be configuring according to the place of installation:

The abstract system is constructed to install in a junction which has 4 roads. But after doing few steps of configuration it can be used in any kind of place.

Our design was done based on the above functionality. I like to describe the steps we go through, First of all the below diagram shows our basic block diagram of the design.

Further steps we have taken to develop the system will be given as following blog posts. Follow them to understand further.time.

Thursday, November 3, 2011

When I went to buy a laptop these days, I identified that there is a serious issue with some Laptops and PCs. So I thought that I have to share what I found. There is a Chipset circuit design issue identified in the Intel® 6 Series Chipsets. It is better to understand what is going on before you buys a new one.

So before you buy a Laptop or PC please read this.
http://www.intel.com/support/chipsets/6/sb/CS-032521.htm

Or before you buy your laptop or PC run CPU-Z on the machine and check the version of the south bridge. If it is B2 you are in trouble.